What role did Israel play in the toppling of Syria's Assad?

Israeli Prime Minister Benjamin Netanyahu said the overthrow of Bashar al-Assad in Syria was a "historic day in the... Middle East" and the fall of a "central link in Iran's axis of evil". He also took part credit for the the fall of Assad, saying it is a direct result of blows dealt to Hezbollah and Iran by Israel. What role did Israel really play in the toppling of Syria's Assad? Answer by FRANCE 24 Kethevane Gorjestani.